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101.
Mirjam MJ Jacobs Ronald G van den Berg Vivianne GAA Vleeshouwers Marcel Visser Rolf Mank Mariëlle Sengers Roel Hoekstra Ben Vosman 《BMC evolutionary biology》2008,8(1):145
Background
The secondary genepool of our modern cultivated potato (Solanum tuberosum L.) consists of a large number of tuber-bearing wild Solanum species under Solanum section Petota. One of the major taxonomic problems in section Petota is that the series classification (as put forward by Hawkes) is problematic and the boundaries of some series are unclear. In addition, the classification has received only partial cladistic support in all molecular studies carried out to date. 相似文献102.
103.
104.
A comment on D Vitkup, P Kharchenko and A Wagner: Influence of metabolic network structure and function on enzyme evolution. Genome Biol 2006, 7:R39. 相似文献
105.
WS Watkins R Thara BJ Mowry Y Zhang DJ Witherspoon W Tolpinrud MJ Bamshad S Tirupati R Padmavati H Smith D Nancarrow C Filippich LB Jorde 《BMC genetics》2008,9(1):1-17
Background
Major population movements, social structure, and caste endogamy have influenced the genetic structure of Indian populations. An understanding of these influences is increasingly important as gene mapping and case-control studies are initiated in South Indian populations.Results
We report new data on 155 individuals from four Tamil caste populations of South India and perform comparative analyses with caste populations from the neighboring state of Andhra Pradesh. Genetic differentiation among Tamil castes is low (RST = 0.96% for 45 autosomal short tandem repeat (STR) markers), reflecting a largely common origin. Nonetheless, caste- and continent-specific patterns are evident. For 32 lineage-defining Y-chromosome SNPs, Tamil castes show higher affinity to Europeans than to eastern Asians, and genetic distance estimates to the Europeans are ordered by caste rank. For 32 lineage-defining mitochondrial SNPs and hypervariable sequence (HVS) 1, Tamil castes have higher affinity to eastern Asians than to Europeans. For 45 autosomal STRs, upper and middle rank castes show higher affinity to Europeans than do lower rank castes from either Tamil Nadu or Andhra Pradesh. Local between-caste variation (Tamil Nadu RST = 0.96%, Andhra Pradesh RST = 0.77%) exceeds the estimate of variation between these geographically separated groups (RST = 0.12%). Low, but statistically significant, correlations between caste rank distance and genetic distance are demonstrated for Tamil castes using Y-chromosome, mtDNA, and autosomal data.Conclusion
Genetic data from Y-chromosome, mtDNA, and autosomal STRs are in accord with historical accounts of northwest to southeast population movements in India. The influence of ancient and historical population movements and caste social structure can be detected and replicated in South Indian caste populations from two different geographic regions. 相似文献106.
Sanchez D; Ganfornina MD; Gutierrez G; Bastiani MJ 《Molecular biology and evolution》1998,15(4):415-426
Arthropodan hemocyanins, prophenoloxidases (PPOs), and insect hexamerins
form a superfamily of hemolymph proteins that we propose to call the AHPH
superfamily. The evolutionary and functional relationships of these
proteins are illuminated by a new embryonic hemolymph protein (EHP) that is
expressed during early stages of development in the grasshopper embryo. EHP
is a 78-kDa soluble protein present initially in the yolk sac content, and
later in the embryonic hemolymph. Protein purification and peptide
sequencing were used to identify an embryonic cDNA clone coding for EHP. In
situ hybridization identifies hemocytes as EHP-expressing cells. As deduced
from the cDNA clone, EHP is a secreted protein with two potential
glycosylation sites. Sequence analysis defines EHP as a member of the AHPH
superfamily. Phylogenetic analyses with all the currently available AHPH
proteins, including EHP, were performed to ascertain the evolutionary
history of this protein superfamily. We used both the entire protein
sequence and each of the three domains present in the AHPH proteins. The
phylogenies inferred for each of the domains suggest a mosaic evolution of
these protein modules. Phylogenetic and multivariate analyses consistently
group EHP with crustacean hemocyanins and, less closely, with insect
hexamerins, relative to cheliceratan hemocyanins and PPOs. The grasshopper
protein rigorously preserves the residues involved in oxygen binding,
oligomerization, and allosteric regulation of the oxygen transport
proteins. Although insects were thought not to have hemocyanins, we propose
that EHP functions as an oxygen transport or storage protein during
embryonic development.
相似文献
107.
Chloe?KB?Mortimer Tansy?M?Peters Saheer?E?Gharbia Julie?MJ?Logan Catherine?ArnoldEmail author 《BMC microbiology》2004,4(1):31
Background
The fliC and fljB genes in Salmonella code for the phase 1 (H1) and phase 2 (H2) flagellin respectively, the rfb cluster encodes the majority of enzymes for polysaccharide (O) antigen biosynthesis, together they determine the antigenic profile by which Salmonella are identified. Sequencing and characterisation of fliC was performed in the development of a molecular serotyping technique. 相似文献108.
109.
Laura Sheard Nat MJ Wright Clive E Adams Nicole Bound Bruno Rushforth Roger Hart Charlotte NE Tompkins 《Trials》2009,10(1):1-5
Many research-funding agencies now require open access to the results of research they have funded, and some also require that researchers make available the raw data generated from that research. Similarly, the journal Trials aims to address inadequate reporting in randomised controlled trials, and in order to fulfil this objective, the journal is working with the scientific and publishing communities to try to establish best practice for publishing raw data from clinical trials in peer-reviewed biomedical journals. Common issues encountered when considering raw data for publication include patient privacy – unless explicit consent for publication is obtained – and ownership, but agreed-upon policies for tackling these concerns do not appear to be addressed in the guidance or mandates currently established. Potential next steps for journal editors and publishers, ethics committees, research-funding agencies, and researchers are proposed, and alternatives to journal publication, such as restricted access repositories, are outlined. 相似文献
110.
A. Laperche Y. Aigu M. Jubault M. Ollier S. Guichard P. Glory SE. Strelkov A. Gravot MJ. Manzanares-Dauleux 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(4):669-684